I recently wrote up a utility to statically check the syntax of SQL for PostgreSQL. It leverages ecpg, the embedded SQL C preproccessor for postgres, to check the SQL syntax, so it uses the exact same parser that is built in to Postgres itself.

You can check it out on github: http://github.com/markdrago/pgsanity. You can give the README a skim to get a better idea of how it works and to get directions for how to install it. Here's a short example of how pgsanity can be used:

$ pgsanity good1.sql good2.sql bad.sql
bad.sql: line 1: ERROR: syntax error at or near "bogus_token"
$ find -name '*.sql' | xargs pgsanity
./sql/bad1.sql: line 59: ERROR: syntax error at or near ";"
./sql/bad2.sql: line 41: ERROR: syntax error at or near "insert"
./sql/bad3.sql: line 57: ERROR: syntax error at or near "update"